Vehicle theft alarm



United States Patent 3,329,935 VEHICLE THEFT ALARM Wallace S. Wiggins,12530 E. Carinthia Drive, Whittier, Calif. 90601 7 Filed Aug. 17, 1964,Ser. No. 389,877

6 Claims. (Cl. 34065) This invention relates to a theft alarm forvehicles, and more particularly, for motor vehicles having some sourceof current, such as an electric battery.

It is a general object of the invention to provide a theft alarm forvehicles of relatively simple construction which can be armed or put ina condition for operation wherein, when so armed, there is no drain uponthe vehicle battery or similar source of current.

Another object of the invention is to provide a theft alarm whereinsimple and efiective means is provided for temporarily delayingactuation of the alarm device, as when the occupant or occupants of thevehicle are leaving the vehicle after it is stopped, and wherein after ashort interval, the alarm will automatically be armed for actuationafter such short interval. In this case, a negligible amount of currentis utilized from the battery, but it is so slight that danger ofweakening the battery is not present.

A further object of the invention is to provide means whereby when thedelayed arming or actuating feature is used, it can be convenientlycompletely disconnected at desired times, such as when the vehicle is tobe parked or placed in storage for a substantial period of time.

Still a further object of the invention is to provide means forindicating to the user of the vehicle that the alarm has not been armedor placed in an operative condition.

The above and other objects will more fully appear from the followingdescription in connection with the accompanying drawing, wherein:

FIG. 1 is a diagrammatic view of an embodiment of the invention in itssimplest form;

-FIG. 2 is a diagrammatic view including the arrangement of FIG. 1, butwith additional features added.

In the circuitry of FIG. 1, the system includes an inertia switch 4,including a spring contact 6, anchored at 8, and having a free endprovided with a weight 10. The anchored end 8 is secured to a portion ofthe vehicle, and when the vehicle moves in any manner, the weightedspring 6 will vibrate and engage an adjustable contact 12. There is afirst single pole, single throw, normally 'closed thermal relay having aset of contacts 14 and a resistance coil 16. There is a second thermalrelay having normally closed contacts 18 and a resistance coil 20. Heatgenerated in the coils 16 and 20 will act upon and separate the sets ofcontacts 14 and 18 respectively when said coils are energized. There isalso an alarm device 22 which may be a horn or other audible signal, andits magnetic actuating relay 24 comprises a coil 26 and an armature 28,the latter being drawn into engagement with a stationary contact 30 uponenergization of the coil 26. A manually actuated signal throw doublepole switch 32, 34 is provided to arm the alarm or place it in conditionfor operation when the inertia switch 4 is closed. 7

With the vehicle at rest, the manual switch 32, 34 is ice closed. Anysubsequent motion of the vehicle, caused by a person getting into it,starting the engine, or moving the vehicle by self-propulsion, pushingor towing, or merely by jostling, will cause the inertia switch arm 6 tovibrate and bring it into engagement with the contact 12 at leastmomentarily. This will complete a circuit from the vehicle battery 36,contacts 6 and 12, and the coil 38, of a magnetic relay having anarmature 40 adapted to engage a contact 42. When contacts 40 and 42 areengaged, the circuit is completed through the contacts 14 of the firstthermal relay 14, 16 and thence to ground as indicated.

When the coil 38 of relay 38, 40 causes contacts 40 and 42 to engage,the inertia switch comprising contacts 6 and 12 will be shorted out.However, the circuit being completed through the first magnetic relay38, 40 and contact 42 to ground through contacts 14, said magnetic relaywill remain energized, and contacts 40 and 42 will remain in contact.

Simultaneously with the closing of contacts 40 and 42, three othercircuits are completed. One is from battery 36 through the coil 26 ofthe magnetic relay 24 through pole 34 of switch 32, 34, contacts 18,contacts 40, 42, and contacts 14 to ground. As this occurs, magneticrelay 24 closes contacts 28, 30 and energizes the grounded alarm signal22. A second circuit is completed from the battery 36 through pole 32 ofswitch 32, 34, through the resistance or heater coil 16 of the firstthermal relay 14, 16, contacts 40, 42 and contacts 14 to ground. A thirdcircuit is completed from the battery 36 through pole 32 of switch 32,34, through the resistance or heater coil 20 of the second thermal relay18, 20, contacts 40, 42, and contacts 14 to ground.

The circuits to the resistances or heaters 16 and 20 of the first andsecond thermal relays being closed, of course heat will be generated insaid coils. The interval required for the heater coil 16 to open itsrelay contacts 14 is considerably greater than that required for theheater coil' 20 to open its relay contacts 18. In other words, thecontacts 18 of relay 18, 20 have opening and closing cycles of muchshorter duration than a single opening and closing cycle of thermalrelay 14, 16. Furthermore, it will be seen that when the contacts 18 ofthermal relay 18, 20 are opened due to the heating of the coil 20, thecircuit through coil 26 of magnetic relay 24 will be opened and contacts28 and 30 in the circuit through the alarm 22 will open, However,thermal relay 14, 16 will remain energized since the first magneticrelay coil 38 is still energized and contacts 40 and 42 are closed,thereby maintaining the circuit through the heater coil 16 of the firstthermal relay 14, 16.

Of course after a predetermined interval of intermittent opening andclosing of the second thermal relay contacts 18, the heater coil 16 ofthe first thermal relay will open its contacts 14 and break the circuitthrough the thermal relay 14, 16, and at the same time, deenergize thecoil 38 of the first magnetic relay 38, 40, as well as breaking thecircuit through the coil 26 of the second magnetic relay 24, and alsocausing contacts 28 and 30 in the audible alarm circuit to open, thusstopping the audible alarm and resetting the system to an armedcondition.

In FIG. 2 there is shown means for delaying arming of the system for apredetermined period after the manual switch 32, 34 is closed. Thisfeature is provided so that to come to rest in an open position.

I provide a normally open thermal relay 43 with its heater or resistancecoil 44 which will .close the contacts of the relay when the coil isheated to a suflicient degree.

I also provide a magnetic relay comprising a coil 46 with a movablearmature 48 movable between fixed contacts 50 and 52. The coil 46alsoacts upon armature 54 which is movable into engagement with a fixedcontact 56. When the first manual switch 32, 34 is closed, the heater 44is energized through the closed contacts 48 and 50, which are engaged.At the same time a pilot light 58 is energized to indicate a prearmedcondition. Since the third'thermal relay contacts 43 are open, no poweris available from the battery 36 to actuate the relay 38, 40, 42.Contacts 54 and 56 are normally open and the ground path from the alarmactuating relay 24 is open and the signal device 22 will not be soundedeven though inertia switch 4 is actuated.

After a desired predetermined interval, the heater 44 will close thethird thermal relay contacts 43 and energize the magnetic relay coil 46swinging its armature 48 from the contact 50 to the contact 52, andsimultaneously, the coil 46 will swing the armature 54 into engagementwith the contact 56.

Engagement of the armature 48 with the contact 52 disconnects power fromthe heater 44 and pilot light 58 and power is supplied through contacts43 to the system as set forth in FIG. 1, so that if the vehicle issubjected to maintained around the open contacts 43 by reason of thecontinued energization of the third magnetic relay coil 46, and thecircuit through its armature 48 and contact 52. Pilot light 60simultaneously indicates an armed condition.

' The third relay coil 46 has also swung the armature 54 into engagementwith contact 56 completing the ground path for relay 24 and the systemis fully armed which may be incorporated if desired. In such event theswitch, including the pole 66, opens the power to the third magneticrelay coil 46 and pilot light 60. Closing of the switch comprising pole68 and contact '76, shorts out the contacts 54, 56.

- In this condition the circuit is similar to and operates exactly likethe form of the circuit shown in FIG. 1, and a there is no current drainwhen the system is armed by closing the first manual switch 32, 34. Ofcourse when the second manual switch 62, 64, 66, 68 is returned to theposition of FIG. 2, the delayed arming feature inv.

cluding the third thermal relay 43, 44 is restored.

FIG. 2 has also provided therein a reminder circuit first manual switch32, 34, whichheretofore hasbeen shown and described as a double polesingle throw switch, can have substituted therefore a triple pole doublethrow switch, which when the poles 32 and 34 are opened, a

I pole 78 is closed against a contact 80. Contact 80 is conreopen upondeenergization of their heater 44, circuit is or prepared for actuationupon closing of the inertia switch 4. In this condition of the circuit,the only drain on the battery is a very slight one through the thirdrelay coil 46 and a pilot light 60, and this battery drain is negnectedto ground through a buzzer 82- Orother desired indicator. Pole 78 isconnected to the vehicle courtesy light or dome light 84 and through itsvehicle door actuated switch 86, to the battery. Thus, when the vehicledoor is i opened, the courtesy light 84 will light as usual but also thealarm82 willibe actuated to inform the operator the first manual switchpoles'32 and 34 are not closed. He thereupon closes poles 32 and 34which opens pole 78 and deactivates the reminder alarm 82. To safeguardthe system I provide a fuse 88 between the battery and the entiresystem, and a second fuse 90 ahead of the first manual the first of saidmagnetic relays and said first and second thermal relays beingenergizable by saidinertia switch and so connected to said first thermalrelay to maintain closed q its contacts and maintain the circuit throughthe first magnetic relay, the inertia switch being connected to saidfirst thermal relay to be shorted out thereby when the first thermalrelay is energized, a circuit through the energized ligible because thethird relay coil 46 and pilot light 60 V have comparatively highresistances.

When the manual switch 32, 34 is opened prior to operation, of the motorvehicle, the third relay coil 46 is deenergized and the system is openor unarmed, providing the return of armature 48 of the third magneticrelay .to the contact 50, which opens the delayed arming feature of thedevice.

Means is provided for converting the above described circuitry in FIG. 2in eifect to that of FIG. 1 in the event the vehicle is to be parked foran extended length of time during which the amount of battery drainthrough the 7 third magnetic relay coil 46 and pilot light 50 mighteventually become appreciable because of the length of time. For suchpurpose I provide a four-pole'single throw switch comprising poles 62,64, 66 and 68 having cooperating 74, In this. position, the third.thermal relay 43, 44 and the third magnetic relay 46, 48, 50 and 52 arein operative condition in the circuit upon closing of the first manualswitch 32, 34 and actuation of the inertia switch 4.

7 contacts 70, 72, 74 and 76. In'the position of this switch I firstmagnetic relay and the coil of the second magnetic relay to close thecontacts of said second relay and activate said alarm device, said firstand second thermal relays having different cycles of operation and beingconnected between the battery and said first magnetic relay,

said manual switch being operable to open and close the 3 circuit tosaid first magnetic relay and said inertia switch.

2. The structure in claim 1, and said first thermal relay having a cycleof greater duration than that'of said sec;

ond thermal, relay and sntficient to span a plurality ;of

cycles of said second thermal relay.

. 3. The structure in claim 1, and means fordelaying the etfectiveoperation of said inertia'switch comprising: an auxiliary circuit havinga normally closed third magnetic relay between said manual switch .andsaid inertia switch and first magnetic relay, and a normally open thirdthermal relay between said first and third magnetic relays,

whereby, when the manual switch is closed, the circuit to.

said inertia switch and alarm device remains open until closed by saidthird thermal relay.

4. The structure in claim 3, and a second manual switch connected aroundsaid thirdmagnetic relay to render inoperative said third magnetic relaywhen said second manual switch is closed.

5 6 5. The structure in claim 1, and means for indicating ReferencesCited that said first manual switch is open and the alarm incapa- UNITEDSTATES PATENTS ble of operation comprising additional switch meansconnected to and actuated by said first manual switch, an 2'8921816/1959 Benson et 340 64 open circuit indicator, and said additionalmanual switch 5 2,984,820 5/1961 Kennen 340-65 zngaziilsldlggzgrg.another contact connected to said open on NEIL C. READ, PrimaryExaminer- 6. The structure in claim 5, and a vehicle door actuated A. H.WARING, Assistant Examiner. courtesy light switch connected between saidadditional manual switch means and its connection with said bat- 10 terycircuit.

1. IN A VEHICLE THEFT ALARM FOR USE WITH A VEHICLE BATTERY, AN INERTIASWITCH, AN ALARM DEVICE, FIRST AND SECOND NORMALLY OPEN MAGNETIC RELAYS,FIRST AND SECOND NORMALLY CLOSED THERMAL RELAYS, A MANUAL SWITCH, ACIRCUIT FROM SAID BATTERY THROUGH SAID MANUAL SWITCH AND INERTIA SWITCH,THE FIRST OF SAID MAGNETIC RELAYS AND SAID FIRST AND SECOND THERMALRELAYS BEING ENERGIZABLE BY SAID INERTIA SWITCH AND SO CONNECTED TO SAIDFIRST THERMAL RELAY TO MAINTAIN CLOSED ITS CONTACTS AND MAINTAIN THECIRCUIT THROUGH THE FIRST MAGNETIC RELAY, THE INERTIA SWITCH BEINGCONNECTED TO SAID FIRST THERMAL RELAY TO BE SHORTED OUT THEREBY WHEN THEFIRST THERMAL RELAY IS ENERGIZED, A CIRCUIT THROUGH THE ENERGIZED FIRSTMAGNETIC RELAY AND THE COIL OF THE SECOND MAGNETIC RELAY TO CLOSE THECONTACTS OF SAID SECOND RELAY AND ACTIVATE SAID ALARM DEVICE, SAID FIRSTAND SECOND THERMAL RELAYS HAVING DIFFERENT CYCLES OF OPERATION AND BEINGCONNECTED BETWEEN THE BATTERY AND SAID FIRST MAGNETIC RELAY, SAID MANUALSWITCH BEING OPERABLE TO OPEN AND CLOSE THE CIRCUIT TO SAID FIRSTMAGNETIC RELAY AND SAID INERTIA SWITCH.